Yeah, guestbooks are still a thing and I’m rocking one. Please feel free to sign my guestbook and/or peruse the entries left by others.
Now that you've moved to Jekyll, are you reconsidering IndieWeb support? It seems one of the main issues you had with it was managing 7+ WP plugins. Adding the necessary metadata to the jekyll templates should be much easier. On the other hand, your other complaint (nobody is using it) stands, although, compared to mainstream social media nobody uses Mastodon either. I'm personally in two minds about the IndieWeb stuff, because I want to like it, but they seem to have over-engineered a lot of it and ignored pre-existing work in the same area.